Orthostatic Systolic Blood Pressure Elevation and Incident Atrial Fibrillation: Insights From the SPRINT Trial

Abstract

Exaggerated orthostatic changes in systolic blood pressure (SBP) were associated with adverse cardiovascular events. We aim to assess the association between orthostatic SBP changes and incident atrial fibrillation (AF). We performed a post hoc analysis of SPRINT (Systolic Blood Pressure Intervention Trial). Orthostatic SBP changes were defined as standing SBP minus seated SBP. Patients were grouped into tertiles of orthostatic SBP changes. We used Cox proportional regression models to assess the association of orthostatic SBP changes with incident AF. Among 8455 participants included in this analysis, 327 incident AF cases occurred during follow-up. After adjusting for age, female, race, smoking, alcohol use, history of cardiovascular disease, history of chronic kidney disease, and body mass index, an SBP increase ≥6 mmHg to standing was independently associated with a 43% higher risk of incident AF (HR: 1.43; 95% CI: 1.07–1.90; p = 0.014) compared to nonsignificant orthostatic SBP changes (>–4 to <6 mmHg). A SBP decrease ≥4 mmHg to standing showed a nonsignificant higher risk of developing AF compared to SBP changes of >–4 to <6 mmHg. In subgroup analysis, the results presented a similar tendency to the main result. Sensitivity analyses also generated consistent results while additionally adjusting for seated and standing blood pressure or heart rate. In this post hoc analysis of the SPRINT trial, exaggerated SBP increase on standing independently predicts incident AF.

Trial Registration: ClinicalTrials.gov identifier: NCT00000620.